Pneumatic hammer.



-V.'B. LANE. PNEUMATIC HAMMER. APPLICATION FILED APR.11,1908.'

Patented Apr. 20, 1909.

' INVENTOR Viaiarlilazze A TTOHNE Y8;

WITNESSES To all whom it may concern:

, VICTOR EDWARD LANE, OF BERWICR, PENNSYLVANIA.

PNEUMATIC name.

Specification of Letters Patent.-

Patented. April 2o, 190

Application filed April'll, 1908. SeriaL No. 426,4 61.

l 3 e it known that LVlCTOR EDWARD LANE, a citizen of theUmted States, and a resident of Berwick, in the county of Columbia and showing tie barrel, the movable sleeve State of Pennsylvania, have invented a new and Improved Pneumatic Hammer, of which the following is a full, clear, and exact description.

My invention relates to pneumatic hammers, the'several objects of my invention being as follows: I, to promote simplicity by discarding all delicate parts, thus insurlng durability under hard usage; II, to provide for a powerful down-stro ing' the shock-or jar so common in pneumatic hammers; III, to render the. hammer, as far as practicable, independent of any specified ressure of air in order to make it-o erative V, to facilitate the removal and repliiceinent ,ofthe barrel; V, to improve the lubrication of certain movable parts; and, VI, to hold therivet-set securely'on the end -of the barrel, to prevent accidents and prevent said set fronrfalling out.

Reference is to be had to the accompanying drawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a longitudinal central section through m Y improved pneumatic hammer,

mounted therein, and the iston serving as the hammer proper and s idably mounted within the sleeve, this view also showing the arrangement of the air valve, .the air in this instance being cut oil; Fig. 2 is a view somewhat similar to Fig. 1, the air in this instancebeing turned on,- this view further showing the piston "as occupying a diilerent position from that which it occupies in Fig. 1; Fig. 3 is a vertical cross section upon the line 3-3 of Fig. 1, looking in the direction of the arrow, and showing the arrangement of the barrel provided with air ducts, means for supporting the barrel, and further showing one end of the movable sleeve; and Fig. 4 is a vertical section upon the line 4-4 of Fig. 1',

looking in. the direction of the arrow, and" showing the arrangement of the air ducts relatively to the barrel, the sleeve and the sleevc26 is further provided :with air passages 33, 33 34 disposed as indicated-in Fig. 1. At 33" and 35't-he barrel 5 is provided with air passages adapted to register with piston.

The barrel of the hammer is shown at 5 and is mounted upon a head 6 provided with e in connection with a cushioned back-stroke, thus eliminatserving as a handle, whereby the entire device may be manipulated. A trigger 9 is disposed within the handle and journale d' upon a pivot 10. The handle is provided with a groove 11 for receivingthe trigger 9 which, when forced into thegroove, be comes practically flush with theinner surface of the handle. Y

A valve passage 12, of cylindrical. form, contains a slide valve 13, the latter being provided with a stem 14, which engages the outer end of the trigger 9. A spring 17 presses against the valve 13 anditends to normally maintain it in the position indicated in Fig. 1, in which instance. the-valve is closed. A cap closure 15 serves'to prevent undue escape of air fromthe passage 12 and to hold the spring 17 in place. An inlet pipe.

is shown at 16 and maybe conl'iected-with a hose or other ilexible'pneumatic supply member. i

The head 6 is rovided with alongitudiniil passage 18 and t e barrel 5 is provided with a longitudinal passage 19, these passages registering with each other andbeingprac tieall continuous. The barrelfp ,is

rovide wit-ha tool holder 20, [in which is mounted a rivet-set 21, provided with a stem 22, the latter working loosely within the tool holder. A pin 23. extends diumetrically throughtl'ie' stem '22 andhas a limited play within a passage 24, this passage communicating with grooves 25 for facilitating the'insertionof the pin 23. c i Slidably; mounted within the barrclb a sleeve 26 provided externally with oil grooves 27. This sleeve 26 is further provided with a closed end 28-, the latter being circumscribed by an annularassa'ge'flt), as indicated in Figs. 1 and 2; hebarr'el 5 is provided with a substantially U-shaped fpas sage 30 communicatin "Exit-h thelcentrali passage 31 of theba'r're Tlre. sle'eve126 -is provided with air passages 32- con niunica'tmg with each other and merging'intoagem eral annular form, these passages being (lis posed in immediate'pr'oximity to" the end '28.

of the same, and at times registers with the] passages 32,, as ind1cated1n'Fig; 1.: The

the passages 33 and 34 respectively, as indicated-in Fig. 2. The sleeve 16 is further. provided with'passages 36 communicating. with each other and adapted to be brought into registry with a port 37, the latter being simply the inturned end of the passage 19 The barrel 5 is further provided with a passage 38 disposed adjacent to the lower or smaller end of the barrel 5. A piston 39, constituting the hammer proper, is provided with striking ends 40, 41, of reduced diameter. The barrel 5 is provided with a passage 42 (see Fig. 3) and this passage'may; e brought into registry with a passage 43 with which the collar 7 is provided, as indicated by dotted lines in Fig. 1 and by full lines in Fig. 3.

The rivet set 21 is normally placed loosely within the reduced portion 20 of the barrel 5 and is adapted to strike the blows when pounded by the piston 39. I

The operation of my device is as follows:

I The air pressure is controllable by aid of the trigger 9. lVhen this trigger is withdrawn toward the handle 8, as indicated. in Fig. 2, the air is turned onfull and the piston 39 has a rapid reciprocating motion. Then, however, the trigger 9 is released, as-indicated in Fig. 1, the air supply is cut off and the piston. is motionless. Starting from the position indicated in Fig. l, we will follow the cycle of operations. The trigger 9 is withdrawn to- Ward the handle 8 to any desired-extent, the

degree of movement of the trigger directing the degree of inflow of the air, and consequently the speed and power-0f the hammer strokes. The valve being open and the parts being inthe position indicated, the air enters through the passages 18 and 32, thereby starting the piston 39 into motion. As soon as this piston has-traveled a distance representing its proximate-length, the 'air behind it passes outwardly through the air passage 33 and backward through the passage 30 into the annular passage 29. This causes the sleeve 26 to move slightly, but as the weight of this sleeve is considerable and the sleeve is at first motionless, it acquires much slower motion'than that of the piston 39. The forward movement of the sleeve 26, however, closes the passages 32, 32 33 and 38,

I and opens the ports 34, 35 36, 37, 33 and This, however, does not take place until after the piston 39 has mactically reached the end of its stroke. The piston strikes a dead blow against the stem 22 of the v rivet-set. By this time (the passage 36 being in registry with the port 37), the air enters through this port and drives the piston 39 back to its starting point. During the return stroke of the piston it is subjected to a full degree of pressure until it moves far momentum, as the air is now this port. The air driven ahead of the piston 39 forms a cushion for the return blow and.

,ries the;passages 33 and 34 enough to clear the port35, but during the rest of the stroke it travels mainly by its vented through thus obviates the necessity for a severe shock. The ports 33" and 33*, being now in registry, cause the air in front of the piston upon'the-back stroke to be released. The an continues to escape through the ports 33 F, 33F, until the piston reaches these ports, the piston being cushioned during the rest of the back strokef When the piston 39 leaves its normal position and starts toward the rivetset, the air in front of the piston has a ready escape through the passage 38.- Upon the finish of the return-stroke, however, the passages 33 a and 35 are closed, because the sleeve 26, in moving away from the rivet-set, car out of registry with the passages 35 and 33 respectively. It will'thus be seen that the piston, while mov ing in the proper direction to strike its blow, is uncushione posite direction is cushioned.

Thile I show the device as equipped with a rivet-set, it will be understood that the lattermay be replaced by any equivalent member. I do not limit myself to the precise construction shown for the various parts of the whereas its motion in the OP? hammer, as they may be varied without departing from the spirit of my invention. As the rivet-setcannot be detached from the barrel except when turned into a definite position, the liability to accidents is greatlydecreased. In instances where the rivet-set is perfectly loose and unconfined, an accidental or unauthorized pulling of the trigger sometimes causes the rivet-set to be forcibly ejected. This is avoided in my dev'ce.

Having 'thus described my invention, I

claim as new and desire to secure by Letters Patent: I

V The combination of{ a barrel provided with a centrally disposed passage, a sleeve mounte'd within said passage'and slidable in rela tion thereto, a. piston, mounted withinsaid sleeve and movable in relation to the same, said piston serving as a hammer, means for applying airpressure to said piston for the purpose of propelling the same, and means for preventing escape of airduring a" part of the return stroke of said pismn for the purpose of cushioning said return stroke thereof. In testimony whereof I havesigned my name to this specification inthe presence of I 1 1 two subscribing witnesses. 1

VICTOR; EDWARD LANE- l/Vitnesses: i L. S. JAooBr,

, .MINNIE WANrpK. 

